Plan B Spotting or Implantation Bleeding: Key Differences Explained

Plan B may cause light-to-moderate bleeding. It may also cause cramps, sore boobs, and nausea. If you suspect pregnancy following Plan B or if your period hasn’t started within 4 weeks of taking it, take a pregnancy test.

Some women report light-to-moderate bleeding after taking Plan B, or the morning-after pill.

The packaging advises that the contraceptive pill can cause periods to be longer or shorter than usual, or you might menstruate at times you didn’t expect.

People don’t usually bleed heavily after taking Plan B, but it’s not unheard of — they might want to have period products within reaching distance after taking it. But spotting doesn’t usually occur between periods after Plan B.

While it has side effects, Plan B can provide peace of mind. Maybe the condom broke. You forgot your pill. Or maybe you just got caught up in the heat of the moment. It happens. But now what? It’s time to talk about Plan B.

The lowdown on Plan B

Conception happens when one of your ovaries releases an eggie (aka ovulation) and that eggie meets up with sperm. The morning-after pill works by delaying ovulation or preventing a fertilized egg from implanting into your uterus.

Plan B can provide mega peace of mind if you aren’t planning a pregnancy, but it does have a few downsides. Some people experience bleeding and other side effects after taking Plan B.

Is there an alternative morning-after pill?

Similar to Plan B, ella (ulipristal acetate) also prevents pregnancy if taken up to 5 days after sex. Some reasons to consider ella:

Like Plan B, it may cause period irregularities. Your period may show up earlier or later or be heavier, lighter, or spotty.

Here’s everything you need to know about the Plan B morning-after pill.

emergency contraception, plan b

According to the drug’s package insert, Plan B can cause fluctuations in your period. That means you might get your period at an unexpected time, or it might be longer or shorter than usual. Most women who take Plan B don’t bleed heavily, but it’s possible.

In a 2006 study of 232 women, only 14.7 percent of participants spotted or bled between periods after taking the morning-after pill.

While light-to-moderate bleeding is normal, you shouldn’t be bleeding heavily.

We cleared up 21 other reasons for spotting between periods here.

There’s not much you can do to prevent bleeding, but you can deal with it just as you would a heavy period.

Be sure to have some period products on hand after you take Plan B, and be prepared for a heavier period than usual. Your cycle should go back to normal the following month.

Stopping regular hormonal contraception can also lead to bleeding — learn more here.

Some folks think heavy bleeding after taking Plan B is normal, but that might be because they’re confusing Plan B with abortion. Plan B doesn’t trigger abortion or miscarriage.

One more time for the people in the back: Plan B is not the abortion pill. Here’s how Plan B actually works.

Plan B is the name brand of the drug levonorgestrel (aka the morning-after pill). Levonorgestrel is a type of progestin, the synthetic version of the hormone progesterone, which your body produces naturally. Science, baby.

The chemicals in Plan B delay ovulation so sperm never meets your egg. If you’ve already ovulated and your egg is waiting in the queue, Plan B prevents the egg from getting fertilized or stops it from attaching to your uterine wall.

We explain how abortion actually works here.

How to take it

Most research shows Plan B has a 52 to 100 percent effectiveness rate. Its success mainly depends on how soon after sex you take it and what stage your menstrual cycle is at.

Plan B One-Step can work up to 120 hours (5 days) after sex, but the sooner you take it, the better. You simply swallow a pill containing 1.5 milligrams of levonorgestrel.

Plan B has no effect on your future fertility, so fear not. When you’re ready to put a bun in the oven, having taken Plan B in the past won’t affect your chances of conceiving.

We give you the full rundown of what to do after having sex without a condom or other barrier method — the important part is not to panic.

How often can I take it?

You can take Plan B whenever you need it. But that’s the thing: It should be about momentary need, not an everyday birth control measure. The more you take it, the more out of whack your cycle will be.

Talk to your doctor about alternative birth control options if condoms aren’t your thing. Plan B isn’t as effective in preventing pregnancy as regular methods of birth control.

If you use Plan B on the reg, you may start experiencing irregular periods. The FDA has reported that as many as 31 percent of women have a heavier period after taking it. That’s because progestin disrupts your regular flow. It can take up to a month for your cycle to get back to normal.

Could I be pregnant?

A bit of spotting after Plan B is normal. But that’s not proof you aren’t pregnant. It could also be implantation spotting. That’s when you bleed a bit when a fertilized egg implants to the lining of your uterus. This usually happens 10 to 14 days after conception.

The only way to know for sure if you’re pregnant is to bite the bullet and take a pregnancy test, especially if your period is late. If you’re pregnant and have taken Plan B, it won’t hurt the fetus. To date, there’s no evidence of Plan B leading to fetal development abnormalities.

Worried about being pregnant? Here’s what you need to know.

On top of an irregular period, here are some other possible side effects of Plan B:

These effects should disappear after a few days. Plan B isn’t linked with any long-term or dangerous symptoms.

While side effects aren’t severe, the pull-out method is one possible method for preventing a pregnancy you might want to consider for next time.

A few factors play into Plan B’s effectiveness. Doctors recommend taking it within 72 hours after a whoopee whoopsy — so you have 3 days to head to the pharmacy and pick it up. If you’re already on birth control, you should keep taking that as you normally would.

Research shows that, while it’s generally effective, Plan B doesn’t have a 100 percent success rate. About 7 out of 8 women who would’ve become preggo won’t conceive if they take Plan B within 3 days after sex. That means 1 out of 8 will get pregnant.

Plan B may not work if you vomit within 2 hours of taking it. Additionally, body size may come into play. It may be less effective in women who have a BMI over 25 or who weigh more than 165 pounds.

But that’s doesn’t mean for sure that it won’t work.